Refrigerating machine



E. FREUNDLICH REFRIGERATING MACHINE Filed May 5, 1921 INVENT OR-z Patented ll, i924.

i o i a n a i w in; t

ERICK FREUNDLIGH,

REFEIGElZ-ATING E.

Application filed May 5,

To all whom it may concern: f

Be it known that l, Enron FsEUNnLiori, a citizen of the German Empire, residing at Dusseldorf, Germany, have invented certain new and useful Improvements in Refrigerating Machines, for which filed an application in Germany Feb. 1 1', 1920, and of which the following is a specification.-

My invention relates to refrigerating machines, more especially of the type operated with overheating, and its particular object is to so combine tiie compressor and the liquid feed pump that this latter be driven directly by the compressor.

Up till now the number of rotations of the compressors generally employed rendered it impossible to let the compressor drive the liquid feed pump directly, such as by making an extension of the piston rod of the compressor act as feed piston for the said pump, for in doing so the liquid would have been accelerated too much. It has merely been proposed to actuate the piston of the pump against the action of a spring by means of the steam pressure prevailing in the compressor.

I succeed in utilizing an extension of the piston rod or" the compressor as the piston of the liquid feed pump, without altering the working speed and dimensions of the compressor piston, by disposing the suction port or ports of the pump near the end of the stroke or near the cover in such wise that the pump will feed liquid only at the lowered speed attained by th piston near the end of its stroke.

Preferably the suction ports of the liquid pump narrow down in the direction towards the pressure valve mounted in the cover in such manner that shortly before the pressure valve opens, the pressure is gradually increased so as to ensure a more gentle opening of the valve.

In the drawings aniied to this specification and forming part thereof a combined compressor and pump embodying my invention are illustrated diagrammatically by Way of example.

In the drawings The figure is a vertical section of my device.

Referring to the drawings, a is the piston rod of the compressor and s is an extension thereof projecting through the cylinder cover and serving as piston of the liquid feed pump. 0 d is the suction chamber of Ito. 461 .22"

the pump, said chamber communion tin 1 ti e pump cha ober by way of one or a plurality of suction ports Z) and a channel 5/ tne pump cover iere is mounted the actuated press. valve 6 The sue ceives the liquid Z serves to car v the pressure chamber drawing, the suction ports I) are reduce width towards the pressure like manner.

This device operates as follows: On the piston s 01 the pump moving in the direction of the compressor the suction ports 6 are uncovered and liquid is sucked into the chamber 0, (Z through pipe 7, the pump chain her 6 being thus filled with liquid. As the piston s returns, first of all the liquid in excess will flow through the suction ports Z9 back into the chamber 0, 03, while such gases as may be present, will escape through channel 9 into part at of the chamber which acts as an air chamber. As the end of piston 5- moves past the suction ports I), owing to the reduced area of these ports a gradual increase of pressure arises which results in the pressure valve 2' opening gently.

After the valve has opened the liquid flows into the pressure chamber a which forms an air chamber and is carried through pipe Z back into the injection or pressure piping of the plant.

l wish it to be understood that l do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

I claim:

1. lln a refri erating machine in combination, a compressor, piston and piston rod in said compressor, a liquid teed pump connected with said compressor, an extension of said piston rod projecting into said pump and forming the piston therein, a suction port in said pump disposed near the end 0 the pressure stroke oi said pump piston corresponding to the minimum velocity thereof and a pressure valve closing said pump, the section of said-port being reduced in the direction towards said valve.

2. In a refrigerating machine the combination with a compressor chamber, and a piston adapted to move in said chamber of a liquid feeding pump connected to said compressor in amal alignment therewith,

and the pressui" n ch nl its a piston chamber in said pump, and of smaller diameter than the oon'iprcssor, a piston in said pump chamber connected to said compressor piston in axial alignment therewith, a suction chamber near the end of the pressure stroke of said pump piston, a pressure chamber beyond the end of said pump piston chamber, and communicating therewith, suction ports between the suction chamber and the pump piston chamber and of endWise decreasine; area, and a control ling valve intermed e said ports apd said pressure chamber, 2 or liquid inrhiction and eduction conduits respectively connectml to said suction and pressure chan'ibers.

3. in a refrigerating machine the coinbinetion With a compressor, and :1 piston movable in said compressor, of a liquid teed pump connected to said compressor, a piston chamber in said pump and of smaller diameter than said compressor, a pump piston connected in axial aliginnent with said compressor piston, a pressure chamber at the free end of said piston chamber, and a suction chamber near the end of the pressure stroke of said pump piston, throttlingly operating communicating passages between said suction and pump piston chambers, an axially displaceuble pressure valve intermediate said passages and said pressure chainiiier and induction and ednction conduits respectively connected to said suction and said pressure chambers.

In testimony whereof I eiiix my signature. V

ERICH FREUNDLTCH. 

